It's even more tricky if it's not well-covered by automated tests, I suppose. :-) There could be a number of methods to forbid the master to rise up from the grave, e.g. voting quorum (or the simplest, but less elegant, solution - a centralized "witness" daemon who does all the work for all the machines). At least MongoDB does the work well, and with almost zero configuration.
My question was about a ready and well-tested solutions, do they exist.
